Python: Counting frequency of pairs of elements in a list of lists
csv, python
Solution
Rather than manually summing frequencies, use `collections.counter` along with `itertools`:
from collections import Counter
from itertools import chain, combinations
meets = Counter(chain.from_iterable(combinations(line, 2) for line in lines))
Where `lines` is an iterable of iterables of names.
Problem
Actually, I have a dataset about a "meeting". For example, A,B,C have a meeting, then the list would be [A,B,C]. Like this, each list would contain a list of members who participated in the meeting. Therefore: line1= (A,B,C) line2= (A,C,D,E) line3 = (D,F,G) ... I just would like to count the number how many times each pair of members meet each other. For example, member A meets C two times from line1 and line2 and member B meets C one time from line1. So, I would like to make a chart like this.. ``` A B C D E F G... A . 1 2 1 ... B 1 . 1 0 C ``` ... I thought it would be easy at the first but I am pretty confused. Please help me and thank you so much in advance.